The use of wireless communications and, in particular, the use of cellular telephony as a means of personal communication is perceived by many as having experienced substantial, if not exponential growth in recent years. While growth and expansion in the use of cellular telephony for personal communication has been phenomenal in many respects, there still exists significant obstacles for expansion of its use to a large segment of the general population.
As in many emerging industries, the cellular telephony industry has been plagued and victimized by the relatively small segment of the public intent on defrauding the service providers or carriers. This relatively small segment of the public has found a variety of means for circumventing these existing safeguards. It is estimated that fraud by these "consumers" costs the cellular industry more than three million dollars per day.
As a result of the rampant growth of fraud in the cellular industry, carriers have been forced to adopt various techniques designed to reduce the opportunities for defrauding the carrier. An obvious method is to limit system access solely to those subscribers deemed highly creditworthy and to maintain listings of those former subscribers who have, in the past, defrauded the carriers. The primary problem with this approach is that it excludes the significantly larger segment of the general population comprised of otherwise trustworthy individuals desiring cellular services who fall short of the highly creditworthy standard. As a result, this approach severely restricts the potential opportunities for growth at a time when further growth is both desired, if not essential, to the expansion of the cellular telephony industry.
Efforts to reduce the relative exposure of the carrier in monetary terms to these unscrupulous practices have also been hindered by the veritable plethora of features and options now available to users of various forms of wireless communication including cellular telephony. Perhaps the most desired feature for the cellular subscriber is the ability to "roam" in areas which are not serviced by the home carrier. These features and options are virtually demanded by the consumer, but the liability associated with the utilization of these features are borne, at least initially, by the home carrier. The home carrier does not, however, retain control over the extent of the use of these features and options in all potential markets since access to a service and feature may be authorized in areas serviced by other carriers without the real time knowledge of the home carrier.
The inability to selectively control access to the various features available to users of wireless communication stems from the fundamental nature of the wireless communications industry and the basic fact that it relies on a network of different carriers in order to provide service of any meaningful geographic scope. Before providing local connectivity to a visiting cellular subscriber, a "remote" or serving carrier first verifies the creditworthiness of the subscriber or, more aptly, verifies that the home carrier accepts financial responsibility for any fees incurred by its subscriber. In this regard, each cellular subscriber is identified by a combination of a discrete Mobile Identification Number (MIN) and a specific Electronic Serial Number (ESN) which are passed from the "remote" cellular carrier to the subscriber's home carrier by existing IS-41 (Rev. A) messaging protocols in response to a request for service by a subscriber roaming within the service area of the remote carrier. Based upon the MIN/ESN, the home carrier electronically verifies whether the cellular subscriber may have access to the requested services.
In particular, the home carrier maintains a Home Locator Record (HLR) associated with each subscriber which provides data relating to the particular subscriber, including data identifying those features and options available to the subscriber. In conventional cellular systems, the Home Locator Record is typically configured, in advance, by an operator and cannot be altered by the carrier during the verification process. Thereafter, upon request for wireless communications service involving a subscriber of the home carrier within the service area of a "remote" serving carrier, the home carrier transmits the subscriber's Home Locator Record to the serving carrier to create the subscriber's Visitor Locator Record (VLR) which defines the type and level of service to be provided to the roaming subscriber.
One method for reducing the exposure of a carrier to fraud would be to provide local, prepaid wireless communications services. In accordance with this approach, a carrier may integrate existing systems utilized for billing purposes, for example, to monitor the actual time used by the cellular subscriber and, when the subscriber is approaching the prepaid limit, correspondingly restrict and/or terminate service, thereby limiting the carrier's relative exposure. The problem with this approach, however, is that the prepaid services must generally be limited to the geographic area served by the home carrier such that the cellular subscriber is not allowed to roam since the extent of usage outside of the home carrier's service area cannot be monitored or restricted.
While a wireless communications system can control call origination by populating the "HOTLINE" field of the subscriber's Visitor Locator Record (VLR) with the telephone number of a switching platform which, in turn, determines if the subscriber has paid in advance for the cellular service, the problems associated with call termination with a prepaid subscriber have not been addressed. In this regard, the problems associated with call termination with a prepaid subscriber are exacerbated in comparison to call origination because an incoming call for the subscriber may be placed directly to the roaming access port of the "remote" serving carrier.
There is, therefore, an existing need in the wireless communications industry and, in particular, in the cellular telephony industry for a wireless communications system and an associated method of operation which permits a carrier to limit its exposure to potential consumer fraud, while allowing subscribers to have access to the full range of features and options, including roaming and, more particularly, call termination with the subscriber while the subscriber is roaming.